Plasma based system for generating antimicrobial coating on flexible polymeric substrates and process thereof

Abstract

A cylindrical magnetron sputtering assembly for coating on a flexible polymeric substrates with an antimicrobial material, said assembly comprising a sputtering setup and a cylindrical magnetron assembly; said cylindrical magnetron assembly being mounted in said sputtering setup: wherein said cylindrical magnetron assembly comprises: at least one cylindrical anode with slots mounted on a top base plate; at least one central target cylindrical cathode positioned at the center of said anode; a mechanical assembly for moving plurality of said flexible polymeric substrates; said mechanical assembly comprising at least one winder, at least one unwinder, plurality of pulleys and plurality of motors; said sputtering setup comprising plurality of magnetic field coils, vacuum chamber and plurality of power supply. Also provided is process for producing antimicrobial coating on flexible polymeric substrates by the cylindrical magnetron sputtering assembly.

We claim: 
     
       1. A cylindrical magnetron sputtering assembly for coating on a flexible polymeric substrates with an antimicrobial material, said assembly comprising a sputtering setup and a cylindrical magnetron assembly;
 said cylindrical magnetron assembly being mounted in said sputtering setup; wherein 
 said cylindrical magnetron assembly comprises: 
 at least one cylindrical anode with plurality of slots mounted on a top base plate; 
 at least one central target cylindrical cathode positioned at the center of said anode; 
 a mechanical assembly for moving plurality of said flexible polymeric substrates; said mechanical assembly comprising at least one winder, at least one unwinder, plurality of pulleys and plurality of motors; 
 said sputtering setup comprising plurality of magnetic field coils, vacuum chamber and plurality of power supply, wherein the plurality of magnetic field coils are positioned outside the vacuum chamber; and 
 wherein the plurality of slots are configured to pass the flexible polymeric substrates in a vertical direction. 
 
     
     
       2. The cylindrical magnetron sputtering assembly as claimed in  claim 1 , wherein said flexible polymeric substrates is selected from the group consisting of fabric, yarn, polymeric filter media substrates, polypropylene, polystyrene, polyethylene, cotton and combinations thereof. 
     
     
       3. The cylindrical magnetron sputtering assembly as claimed in  claim 2 , wherein said assembly coats moving fabric or moving yarn with said antimicrobial material. 
     
     
       4. The cylindrical magnetron sputtering assembly as claimed in  claim 3 , wherein said mechanical assembly moves said fabric in vertical direction or said yarn in horizontal direction. 
     
     
       5. The cylindrical magnetron sputtering assembly as claimed in  claim 3  wherein said antimicrobial material is uniformly coated with a thickness of 50-100 nm on said yarn or said fabric. 
     
     
       6. The cylindrical magnetron sputtering assembly as claimed in  claim 1 , wherein said antimicrobial material is copper, zinc, or titanium. 
     
     
       7. The cylindrical magnetron sputtering assembly as claimed in  claim 1 , wherein said antimicrobial material is nano copper oxide. 
     
     
       8. The cylindrical magnetron sputtering assembly as claimed in  claim 1 , wherein said assembly operates in vacuum at 10 −2  mbar to 10 −1  mbar and in combination with a DC power supply of −600 to −800 Volts under gas environment. 
     
     
       9. The cylindrical magnetron sputtering assembly as claimed in  claim 2 , wherein said fabric coated with said antimicrobial material is used as clothing, surgical garments, dressings, or bandages. 
     
     
       10. The cylindrical magnetron sputtering assembly as claimed in  claim 2 , wherein said yarn coated with said antimicrobial material is used as fabric, medical bandages, dressing gauges, or antimicrobial filters. 
     
     
       11. The cylindrical magnetron sputtering assembly as claimed in  claim 2 , wherein said polymeric filter media substrate is used for air purification, water purification, or combinations thereof. 
     
     
       12. A process for producing antimicrobial coating on a flexible polymeric substrates by the cylindrical magnetron sputtering assembly as claimed in  claim 1 , said process comprising the steps of:
 a) generating a low pressure plasma in the cylindrical anode to sputter out an antimicrobial material from the target cylindrical cathode, 
 b) generating magnetic field by said magnetic field coils to increase electron density for sputtering, 
 c) performing an unwinding and a winding spool mechanism with said motors inside said vacuum chamber, and 
 d) moving said flexible polymeric substrates multiple times through said cylindrical magnetron assembly to deposit a coating of said antimicrobial material of thickness of 50-100 nm. 
 
     
     
       13. The process as claimed in  claim 12 , wherein said flexible polymeric substrates is selected from the group consisting of fabric, yarn, polymeric filter media substrates, polypropylene, polystyrene, polyethylene, cotton and combinations thereof. 
     
     
       14. The process as claimed in  claim 12 , wherein said antimicrobial material is copper, Zinc, or Titanium. 
     
     
       15. The process as claimed in  claim 12 , wherein said antimicrobial material is nano copper oxide. 
     
     
       16. The process as claimed in  claim 12 , wherein said coating is performed in vacuum at 10 −2  mbar to 10 −1  mbar and in combination with a DC power supply of −600 to −800 Volts under gas environment. 
     
     
       17. The cylindrical magnetron sputtering assembly as claimed in  claim 3 , wherein said moving fabric is woven or non-woven. 
     
     
       18. The cylindrical magnetron sputtering assembly as claimed in  claim 1 , wherein said flexible polymeric substrates is fabric, yarn, or combinations thereof. 
     
     
       19. The cylindrical magnetron sputtering assembly as claimed in  claim 8 , wherein said gas environment is argon or oxygen. 
     
     
       20. The process as claimed in  claim 16 , wherein said gas environment is argon or oxygen.